Building Your Own Drivers?

students asks: "I want to cheaply demonstrate how speaker 'drivers' (the part that makes the noise, not software...also known as a cone) work, not to produce ideal sound. Some quick research has made it clear that it's easy to find directions on how to build a fancy speaker box, but not much on how to make a driver. Unfortunately, I can't use Sake. I also can't get the thin wood. Does anyone know how to build a driver out of home materials?"

Seriously tho

[n1ywb]

A driver is just a solonoid connected to a paper cone. Look up how solonoids are constructed and you should get a pretty good idea of how to procede.

Sure. Here you go.

[FreeLinux]

Here are the instructions you need to make a speaker. [cranbrook.edu]

Build your own driver

[Cthefuture]

Hmmm, there really isn't much to a driver. It's basically just a coil of wire attached to a suspended structure (the cone) that sits inside a permanent magnet. The energy is fed to the coil which makes it move inside the magnet which in turn moves the cone structure to create air pressure waves (sound).

Simple science-type experiments are super easy to do. No more complex than an electric motor experiment.

Although I haven't read it, this [howstuffworks.com] probably has everything you need.

Pictures say a 1000 words

[sweede]

http://www.silcom.com/~aludwig/images/driver.gif [silcom.com]

You will have to create your own motor (magnet + former), your own cone and your own suspension (spider and suround)

get a few donut shaped magnets amd glue them together, a paper tube wrap some thin magnet wire around it secure it with epoxy. get a hunk of round steel and a thin plate. attach the steel to the center of the plate, put the magenets around the pole peice and attach to the plate. add another steel plate to the top with a hole big enough that the former fits in.
thats your motor

make a spider from something. get a paper cone and attach it to the spider to the former to the surround to the frame. and your done !

Or, you can get a cheap $10 speaker from partsexpress.com and use that as an example with good drawings

Here's an example...

[arfonrg]

http://users.ev1.net/~arfonrg/SimpleSpeaker.jpg

9th and 10th grade science lesson

[Mercenary_56]

Here is a science lesson (meant for high school students) on how to make a speaker. You can download the doc here [prek-12engineering.org] or use Google's cache here. [66.102.7.104]

Re:Pictures say a 1000 words

[ivan256]

I made one once back in grade school as a science fair type of project. We used a glass jar as the frame, and some cloths hanger to suspend it so it was all visible. It sounded.... interesting. The jar directed the sound quite well, but it sounded like the whole thing was in a deep hole in the ground. Great for demonstration purposes though. using the jar ring (it was a ball style jam jar) and hanger made it so you don't need all that stuff about the metal plates.

Re:Build your own driver

[unitron]

The permanent magnet and the coil *are* an electric motor, (or generator, depending upon whether they drive or are driven, that is, in audio, whether they are part of a speaker or part of a microphone), and are commonly known as a voice coil due to most early development being done as part of the development of the telephone.

Voice coil motors are not limited to audio work, however. One notable example is the replacement of stepper motors in hard drive head positioning systems.

Not all voice coil operated loudspeakers rely on a permanent magnet. Way back when in the days of vacuum tube radios many sets used a second coil to provide the fixed magnetic field against which the voice coil's changing magnetic field worked. This other coil was energized by using it as the series inductor in the power supply filter, thus saving money and weight by using one part for two functions.